A few days ago we posted some preview performance numbers from the LG Optimus G with Qualcomm's Snapdragon S4 Pro APQ8064 quad core Krait SoC at 1.5 GHz. While OpenGL ES 2.0 performance was where it should have been, one of the things that stuck out was that JavaScript performance in both sunspider and Browsermark was not near where what I was expecting. As always, there's always that caveat which we make note of when testing pre-release hardware that things will change prior to launch, and in this case performance in some areas will increase in the final shipping LG Optimus G software.

I had a long discussion at dinner with LG software engineers responsible for the stock browser, who noted that JavaScript performance will indeed improve in the final shipping version. They let me play with and test an LG Optimus G with an updated software preload running a newer version of the stock browser, with the latest of Qualcomm's V8 JavaScript engine libraries. The software version provided on the LG Optimus G I've been using for the past few days and used for testing was the latest at that time, but still not final, and included an older version of Qualcomm's V8 library. I've re-run the two tests and things have indeed improved.

I discussed stock browser performance for some time with LG's software engineers, and asked specifically about why OEMs change the stock browser. They explained that often the app gets tweaked to improve stability and performance compared to the stock Android browser, fix rendering errors that they've identified in numerous popular Korean portal pages, and of course make changes to the UX they feel are necessary. Getting to the final browser shipping state is often a function of making tradeoffs between stability and performance, and in the case of JavaScript that means including Qualcomm's V8 JavaScript engine libraries in the browser APK, which were updated in the LG Optimus G I re-tested this evening. I was told that there are going to be more tweaks as well before the final shipping software is ready, as the handset isn't in mass production quite yet. There are some other features possibly coming as well, specifically WebGL in the future for the LG Optimus G, and possibly at launch for other upcoming LG phones.

The other major browser-related feature I got a chance to see today was a feature requested by myself and other tech journalists during LG's event this week: Q-Slide for YouTube. If you haven't followed, LG has included a feature they've dubbed Q-Slide which allows for full screen video to be played via an overlay with user-controllable transparency atop another application. The use case they're targeting specifically is one which is very popular in Korea – watching TV DMB (Digital Multimedia Broadcasting) content while on public transportation alongside messaging or browsing the web.

Well, in addition to the aforementioned updated V8 library inside the version of the browser I was shown was the ability to use Q-Slide for any YouTube video or HTML5 Video element video as well. Since the European and US markets don't have any equivalent to DMB, Q-Slide needs to be compatible with other video playback sources beyond the stock player, and the browser team worked to make this compatible before launch.